Malignant degeneration in a juvenile nasopharyngeal angiofibroma has been reported in the literature in only four patients. All of these persons had been previously treated for cure with gamma irradiation. The case report of a 47-year-old man with a 31-year history of nasal obstruction is presented. A recurrence excised 18 months after initial removal of an angiofibroma revealed the surprising diagnosis of fibrosarcoma.